Suppose White has only a queen, bishop, and king, and Black has only his king. Then White can win using the same setup as in "King and Two Queens vs. King." (Of course, if kings are not connected, then the win is trivial as in "King and Queen vs. King".) Note that this setup must be done in a corner whose color is opposite of the color squares the bishop is on. For example, consider:
8/8/8/8/8/8/Bk6/KQ6 b
Black to Move and White to Win
1. ... Kc3 (1. ... Ka3 2. Qb2+ Ka4 3. Qb4# loses faster) 2. Qb2+ Kd3 3. Qc3+ Ke4 4. Qd4+ Kf5 5. Qe5+ Kg4 6. Qf4+ Kh3 7. Qg3#
To put up a little more resistance, Black should try to enter the setup with White to move. For example, consider:
8/8/8/8/8/kB6/8/KQ6 b
Black to Move and White to Win
1. ... Ka2 2. Bc4 Ka3! (2. ... Kb2 3. Ba2 plays into White's hands). Now it turns out that Black can keep avoiding the b2 square at the right times. Let's watch White continue to struggle to get into the setup with Black to move: 3. Qa2+ Kb2 4. Bd3 Kb1 5. Be4 Kc1! (Black uses the c1 square now like he used the a3 square earlier).
White's solution to this little problem is of course quite easy: get into the setup not paying attention to Black. If it is White's move, then he will triangulate his queen like in "King, Queen, and Knight vs. King." Consider again:
8/8/8/8/8/kB6/8/KQ6 b
Black to Move and White to Win
1. ... Ka2 2. Bc4 Ka3 3. Ba2 Kb2 4. Qc1 (trying to triangulate the bishop instead is useless as Black can utilize the a3 square to avoid it) Kb1 5. Qc2 Kb2 6. Qb1 and now it is Black's move and White will win as described earlier.